Fastening component, in particular a spacer element

ABSTRACT

A fastening component, a spacer element in particular, for structural components such as heat shields ( 25, 37 ) with a strip-like enclosing element ( 1 ) for application in certain sections on a heating element ( 3 ) to be shielded, has on the enclosing component ( 1 ) spring-loaded connecting components ( 21 ) by means of which the enclosing element ( 1 ) may be fastened on the heating element ( 3 ) so as to be stationary.

The invention relates to a fastening component, in particular a spacerelement, for structural components such as heat shields.

Structural components such as heat shields which form a shielding systemor part of a shielding system are widely employed in motor vehicletechnology in particular in order to protect heat-sensitive structuralelements such as sensors, fuel lines, pressure sensors, etc. fromthermal overloading. While the heat developed by an economicalperformance-optimated diesel engine on the cylinder or crankshafthousing may be low, such is by no means the case with “hot zones” suchas those in exhaust gas manifolds, turbochargers, catalytic converters,etc., so that heat shields must be present in the appropriate places.This applies especially in the area of catalytic converters, whichrepresent strong heat sources because of their high temperature inindividual phases.

Heat sources such as these often necessitate more or less completeencapsulation, it being essential for the heat shields forming theencapsulation to be fastened in a predetermined position, the spacingdesired between the heat shield and the hot heating element beingensured at least in partial areas. It is found difficult in manyinstances to meet this requirement. What may be involved, for example,are installation situations in which there are no fastening options forunambiguous positioning of heat shields. Assembly itself of heat shieldsmay also be difficult and time consuming because sufficient free spaceis not available in a particular engine compartment.

In connection with these problems the object of the invention is toprovide a fastening component permitting fastening of the structuralcomponents in question in a clear-cut position a distance from a heatingelement at low installation cost.

It is claimed for the invention that this object is obtained by means ofa fastening component according to patent claim 1 in its entirety.

The invention accordingly provides that the fastening component has astrip-shaped enclosing component which in turn may be mounted on theheating element by means of spring-loaded connecting components. Theenclosing element may thus be “clipped” onto the heating element by asimple and convenient method. This may also be accomplished with lowinstallation cost in the event of confined spatial relationships. Theclipped-on enclosing element then forms the base, that is, the primarymounting positions, for suitable heat shields, for example, for thepurpose of effecting encapsulation of a catalytic converter forming aheating element.

By preference the enclosing component is in the form of a band clamp thelength of which is such that it encloses the outer circumference of theheating element, such as the round body of a catalytic converter, overapproximately one-half of the enclosing length. An enclosing componentof this shape makes it convenient to clip the component on from the sideand ensures adequate fixation on the heating element, in particular if,as claimed for the invention, an advantageous exemplary embodiment, theconnecting components are in the form of leaf tension springs whichextend away from both ends of the band clamp as extensions of thelatter.

By preference the tensioning springs are shaped so that they are intensioning contact with the enclosed heating element by way of one freeend and so that they are bent outward away from the heating elementbetween the tensioning area and its free end. In addition to theirtensioning function proper, that is, fastening the enclosing component,the tensioning springs may also form a spacer element for a heat shieldby their end area bent outward and/or may be engaged with such a shieldin such a way that an anchorage is formed which is flexible or maypermit a specified relative movement of the heat shield.

In especially advantageous exemplary embodiments the band clamp formingthe enclosing element is shaped in partial length areas following thetrace of the outer circumference of the heating element and in otherpartial length areas is provided with bending sections for extension ata distance from the heating element. Hence, suitable configuration ofthe bending sections results in simplicity in production of spacerelements for heat shields in contact with such elements.

By preference the band clamp has on both ends a bending section spaced adistance from the heating element. The configuration may be such thatthe tensioning springs extend from an area of the bending sectionsspaced a distance from the heating element areas diagonally to the outersurface of the heating element. This makes available a spring pathsuitable for compensating for thermal dimension changes.

In exemplary embodiments in which the band clamp has on both ends anextension bending at an angle outward from the outer circumference ofthe heating element enclosed, such extensions may form fastening pointsfor built-on components such as heat shields, for example, by provisionon the extensions of at least one threaded opening, preferably with anut mounted on it, for formation of a screw coupling.

The configuration arrived at may be such that a screw connection elementspaced a distance from the heating element for fastening a second heatshield is provided on the band clamp in the area of the ends between thebending sections of the latter.

It is especially advantageous for the configuration arrived at in anexemplary embodiment such as this to be such that the first and thesecond heat shield form at least partial encapsulation of approximatelyone half of the enclosing areas of the heating element positioneddiametrically opposite each other. This results both in essentiallycomplete encapsulation of the heating element involved and in cohesionof the shielding system formed in this manner, in that fastening of theheat shields results both from closed linkage of the enclosing componentby means of the tensioning springs and from the circumstance that thetwo heat shields connected to the enclosing component enclose(encapsulate) the heating element on sides opposite each other.

The enclosing component may be produced simply and cost-efficiently byforming the strip-shaped band clamp and the tensioning springs servingas spring-loaded connecting components in one piece, preferably ofhigh-grade steel possessing elastic properties.

The invention will be described in detail in what follows on the basisof an exemplary embodiment illustrated in the drawing, in which

FIG. 1 presents a perspective oblique view of an exemplary embodiment ofthe fastening component claimed for the invention mounted on acylindrical catalytic converter housing, only a partial length area isshown;

FIG. 2 an end view drawn on a larger scale than that in FIG. 1, of theopen end of a catalytic converter housing, there being connected to thefastening component a first and a second heat shield which constituteencapsulation of the catalytic converter housing;

FIG. 3 a diagonal perspective view much larger than that in FIG. 2showing only the area designated as III in FIG. 2, a screw connectionbetween the fist heat shield and the fastening component being shownonly in part;

FIG. 4 the partial length area shown in FIG. 1 of the catalyticconverter housing with heat shield mounted on it, its screw connectionto the fastening component not being shown, and

FIG. 5 a presentation similar to that of FIG. 4, but of the second sideopposite that of the heat shield of FIG. 4, with the heat shieldconnected to the fastening component.

The invention will be explained in what follows on the basis of anexemplary embodiment in which the fastening component claimed for theinvention for positioning of structural elements is provided in the formof a first and a second heat shield which forms an encapsulation on theouter side of the catalytic converter. The invention is, of course,suitable for positioning of structural elements of other kinds.

FIG. 1 illustrates the fastening component in the form of a band clamp 1in the form of a sheet metal possessing elastic properties, bypreference of stainless steel. The band clamp 1 is fastened to elasticparts (not shown in FIG. 1) described in detail in what follows, withreference to FIGS. 2 and 3, on the cylindrical outer circumference ofthe catalytic converter 3. As is to be seen in FIG. 2, the measuredlength of the band clamp 1 is such that it extends over approximatelyone-half of the circumference of the catalytic converter 3. Each of thetwo ends 5 of the band clamp 1 has a flat extension 7 projectingradially outward in relation to the circular curvature of the band clamp1.

As is shown in FIG. 2, and especially in FIG. 3, the band clamp 1 doesnot have over its entire length a circular extension following theexternal circumference of the catalytic converter 3 but rather hasbending sections at which the band clamp 1 is spaced a distance from theenclosed catalytic converter 3. Such is the case of the area of lengthpositioned in the center between the ends 5, where there is formed bybending sections 9 and 11 (FIG. 2) a level section of length 13 radiallyoffset outward which forms a spacer element and a support for a boltingelement 15. In addition, there is in front of each end 5 of the bandclamp 1 a bending section 17 displaced radially outward by the ends 5 ofthe band clamp, so that a spacer element is formed, of which one,designated 19, is to be seen in FIG. 3.

At each end 5 of the band clamp 1 there extends from the spacer element19 a length of a flat tensioning spring 21 serving as an extension ofthe band clamp 1. As is shown with particular clarity in FIG. 3, therespective tensioning spring 21 extends diagonally radially inward andadjoins a tensioning area 23 under spring tension on the outercircumference of the catalytic converter 3. If the band clamp 1 isclipped onto the catalytic converter 3 from the side, that is, into theposition shown in FIG. 1, the band clamp 1 is immobilized on thetensioning area 23 by the force of tensioning springs 21.

As a further development of the mounting process for encapsulation ofthe catalytic converter 3 a first heat shield 25, which, as is to beseen in FIG. 4, is more or less in the form of a half-shell, isconnected to the band clamp 1 clipped onto the catalytic converter 3. Ashas already been pointed out, the band clamp 1 has on each of its ends 5an extension 7 running outward at a angle. These extensions form amounting position for the first heat shield 25, which, as is to be seenin FIG. 4, analogously to the extensions 7 of the band clamp 1, hasextensions 27 extending at an angle laterally outward. These extensions27, provided with bolt holds, may be bolted onto the extensions 7 on theband clamp 1, specifically, by means of a bolting fixture which in eachinstance has a forced in nut 29 and fixing bolt 31 (the latter has beenomitted from FIG. 3).

As is shown the most clearly in FIG. 3, the flat springs 21 are bentradially outward in an arc in their section extending to the free end 33and adjoining the tensioning area 23 and are engaged by their outer end33 in a recess 35 (shown only in FIG. 3) in the first heat shield 25.The dimensions of the recess 35 are such that a relative movement may beexecuted in the circumferential direction in order to compensate forthermal changes in dimension. As is to be seen in FIGS. 2 and 4, theheat shield 25 is provided with local curvatures and shaped so that itsinterior is spaced at least in some sections a distance from thecatalytic converter 3 enclosed.

In order to complete the encapsulation, there is presented in FIG. 5 adiagonal elevational view of a second heat shield 37 which, like thefirst heat shield 25, forms a partial shell, fastened to it by means ofthe locking element 15 on the band clamp 1 (the part of total boltingelement operating in conjunction with the bolting element for the secondheat shield 37 is not shown in the figures). As is illustrated by FIG. 2in particular, not only is the second heat shield 37 on the band clamp 1immobilized by way of the bolting element 15 but also spaced at adistance from the catalytic converter 3 engaged by the spacer elementsof the band clamp 1, which arise from its bending sections 9, 11, and17. The band clamp 1 itself is fixed not only in position on thecatalyst 3 both by the tensioning springs 21 but is secured from pullingaway from the catalytic converter 3 in that the first heat shield 25encloses the area surrounding the catalyst 3 not enclosed by the bandclamp 1. The second heat shield 37, which is associated with the areaenclosing the catalytic converter 3 surrounded by the band clamp 1, alsois unequivocally fixed in position by the connection with the boltingelement 15 and is spaced relative to the catalytic converter 3 asdesired a distance from the surrounded catalytic converter 3 by means ofspacer elements (19 in FIG. 3 and section 13 in FIG. 2).

1. A fastening component, in particular a spacer element, for structuralcomponents such as heat shields (25, 37) having a strip-like enclosingcomponent (1) for application in certain sections to a heating element(3) to be shielded and having spring-loaded connecting points (21)provided by means of which the enclosing component (1) may be fastenedon the heating element (3) so as to be stationary.
 2. The fasteningcomponent according to claim 1, characterized in that the enclosingcomponent is in the form of a band clamp (1) the length of which isdimensioned so that it surrounds the outer circumference of the heatingelement (3) in part, by preference to approximately one-half theenclosing length.
 3. The fastening component according to claim 2,wherein the connecting components are in the form of flat tensioningsprings (21) which extend away from the band clamp (1) as extensions ofsuch band clamp.
 4. The fastening component according to claim 3,wherein the tensioning springs are in a form (21) such that they areapplied under spring tension to the heating element (3) by way of atensioning area (23) on the heating element (3) enclosed and whereinthey are bent outward area away from the heating element (3) between thetensioning area (23) and their free end (33).
 5. The fastening componentaccording to claim 4, wherein the band clamp (1) is shaped in partiallength areas so as to follow the course of the outer circumference ofthe heating element (3) and in other partial length areas is providedwith bending sections (9, 11, 17) for extension at a distance from theheating element (3).
 6. The fastening component according to claim 5,wherein the band clamp (1) has on both ends (5) an end bending section(17) spaced on each end thereof a distance from the heating element (3).7. The fastening component according to claim 6, wherein the tensioningsprings (21) extend from an area (19) spaced at a distance from theheating element (3) of the end bending sections (17) to the tensioningarea (23) diagonally to the outer surface of the heating element (3)enclosed.
 8. The fastening component according to claim 2, wherein theband clamp (1) has on both ends (5) an extension (7) extending from theouter circumference of the enclosed heating element (3) to the extensionbent outward which forms fastening points for built-on components suchas heat shields (25).
 9. The fastening component according to claim 8,wherein the fastening points on the extensions (7) are provided, forformation of a threaded joint, with a heat shield (25) having at leastone screw hole, preferably with a forced-in nut (29) mounted thereon.10. The fastening component according to claim 9, wherein there isprovided on the band clamp (1), in the area of bending sections (9, 11)between its ends (5), a bolting element (15) spaced a distance from theenclosed heating element (3) for fastening of a second heat shield (37).11. The fastening component according to claim 10, wherein each of thefirst and second heat shields (25, 37) forms at least in part anencapsulation of approximately one-half the enclosing areas of theheating element (3) diametrically opposite each other.
 12. The fasteningcomponent according to claim 2, wherein the strip-like band clamp (1) isformed to be integral with the spring-loaded connecting springs (21), bypreference a band clamp of a stainless steel possessing elasticproperties.